In the prior art, a dedicated stapler cassette has been manufactured for each of staples having needle legs of different lengths. This stapler is loaded for different applications with stapler cassettes for different needle leg lengths.
A stapler cassette has been proposed by us in JP-KOKAI (unexamined patent publication)-HEI07-96475. In a stapler cassette 31, as shown in FIG. 10, a frame 32 is provided at its leading end with a cap 33, and accommodates a guide 34 loaded with staples 35. In the guide 34, there is fitted a pusher head 37, which is attached to the leading end of a pusher spring 36 so as to slide the rear end of the staples 35 back and forth. The staples 35 are pushed at all times toward the cap 33 by the pusher head 37. Numeral 38 designates a rear end cap of the pusher spring 36.
The staples 35 stored in the stapler cassette are extruded down by the downward push of the cap 33.